This invention relates to radar PRF measurement and sorting of unknown electromagnetic emitters and more particularly to PRF digital readouts.
All electronic intelligence (ELINT) gathering systems require on-board signal processing if useful information is to be derived from complex electromagnetic environments. Intercepted electromagnetic signals can be classified and sorted according to signal parameters such as radio frequency (RF), pulsewidth, and PRF. Signal separation using RF as a sorting parameter has been used quite successfully; however, it is now common for many different types of emitters to use the same RF band. For most ELINT environments the second most useful sorting parameter is the PRF. Unfortunately, the processing equipment available to the Fleet operator has been very meager in terms of PRF accuracy and resolution. If an operator sets out to monitor activity at a certain PRF, about the only PRF filter available has been that between his ears. The pulse analyzers available have been analog scale devices with little more than 5% accuracy and even this accuracy has been doubtful for multi-signal environment.